First off, thanks to kglad for the line graph function I
started with, it has been a huge help. Now the step I'm trying to
take is 2 fold.

First, I'd like to graph more than one line segment on the
graph. Right now I am graphing functions f1 and f2, but f2
currently overwrites f1. I want them to coincide so f1 goes from
x=1 to x=15, f2 goes from x=15 to x=25, f3 goes from x=25 to x=10
at a different y (these are all curves), and finally f4 goes from
x=10 to x=1 creating a closed shape. Also, I want the x values and
the y values to be variable based on the temperature. I'm using
PV=nRT and n, R, and T are all known. so I have something like
P=nRT/V where P is y, V is X and the nRT can be calculated for two
steps of the 4. The other two steps are adiabatic, so Q=0, I don't
know yet how to fit the lines but i do know that y = a / (x^(5/3))
is a formula that works, I just need to find the proper a values
for steps 2 and 4.

Part two of this issue is that currently the graph is drawing
as the whole canvas, which is fine for testing until i get the
multiple line part worked out; however I only want this to be 1/4
of the viewing area as I have other movie clips and such to put on
this. A conceptual drawing of what I plan on making can be found
at:
http://www.students.bucknell.edu/gbement/Steps.html

I'm a novice to Actionscript and movie clips, I previously
did everything with motion tweens and nothing was dynamic. I plan
on creating the piston and molecule simulation in another movie
clip, then I can vary the play speed relative to the hot and cold
temperatures by looping the movieclip and having it play faster for
a high T and slower for a low T.

Any help on any of my many issues would be greatly
appreciated and the user will be recognized for their assistance in
my research presentation :)

That certainly did help some. I'll try and combine the
snippet you gave me with the one I found from kglad and if i figure
it all out i'll have axis and graphs and it'll be pretty awesome.
I'll post back with my progress and my code snippets if I get
anywhere farther. Thanks a lot Arun!

Hi Arun, thanks again for the help but upon closer inspection
(along with only a basic knowledge of java and actionscript), I
think your script would need editing to work for me (editing i'm
unsure of how to do). What I'm looking for is a graph that will
create a line based on a function. Much like y=(a*b*c)/x or
y=(a*b*c)/(x^1.66) The a*b*c would be complicated also, but here's
what i've thought up on paper that I have to move to script, I hope
this is useful:

Step 1: Calculate the a*b*c
The original function is PV=nRT , nRT being the a*b*c ,
however the Thot and Tcold terms are input boxes that the user
types in before hitting the "go" button.

Then I need to find a way to initialize axis to line the
graph, I can label the P and V axis using static text boxes later I
suppose.
The problem I have with yours that I don't understand is that
I could add the function into the y part of the addLine() function,
however it's noted as inity= y1 (requires a number), and the
function definition has y1:Number.

Now the issue i'm tackling below is just a newbie's lack of
understanding (i hope), but the script kglad wrote (snipped below)
will graph one line, and i can't figure out for the life of me how
to write this up to graph more than one instance without
overwritting the previous line. Again, Thanks for the help so far,
it has helped me find the points where I lacked direction and solid
ideas before.